USC scientists have made a groundbreaking discovery about the nature of the Earth's enigmatic inner core, revealing for the first time that this 1,500-mile-wide ball of iron and nickel is changing.

Scientists found that the inner core’s structure changes as it rotates. It deforms at its border, potentially accumulating more material in some areas and less in others — almost like creating hills and valleys.

The surface of Earth's inner core appears to be dynamic, changing shape as it rotates, earthquake waves reveal.